1. Field of the Invention
The present invention relates generally to the field of sound systems and more particularly to a method and apparatus for correcting acoustic distortions in the recording or playback of audio material introduced by the room environment in which the recording is made and/or played, as well as in the associated transducer and electronic systems.
2. Description of the Prior Art
Prior to the present invention it has been well known that the acoustic properties of a room have an effect upon sound both during recording and during playback of a recording. Each room will exhibit unique combinations of properties depending upon the size, shape, finishing materials and contents of the room. This is evidenced by the capacity of some trained musicians to identify the location at which a recording was made simply by listening to the recording. Additional distortion is introduced by the non-uniform frequency response of microphones, loudspeakers and associated components, any of which may impart a coloration to the reproduced sound as perceived by a listener.
In the recording studio elaborate steps are taken to minimize the acoustic effects of the room environment. The ultimate such step would be to perform the recording in an anechoic chamber, however, such extreme would be prohibitive in cost and would sound unnatural due to the lack of any reverberations. For the listener of sound recordings little has been done to correct the acoustic distortion introduced by the room environment in which the recording is played. Some benefit is gained through the use of presently available graphic equalizers which typically provide one gain control per octave per stereo channel. Even a cursory analysis of the potential resonances in a typical sized room reveals thousands which are closely spaced throughout the audio spectrum. To balance these resonances individually with a graphic equalizer would require a corresponding number of gain controls which would become impossible of operation.